In robotically-assisted or telerobotic surgery, the surgeon typically operates a master controller to remotely control the motion of surgical instruments at the surgical site from a location that may be remote from the patient (e.g., across the operating room, in a different room or a completely different building from the patient). The master controller usually includes one or more hand input devices, such as joysticks, exoskeletal gloves or the like, which are coupled to the surgical instruments with servo motors for articulating the instruments at the surgical site. The servo motors are typically part of an electromechanical device or surgical manipulator (“the slave”) that supports and controls the surgical instruments that have been introduced directly into an open surgical site or through trocar sleeves into a body cavity, such as the patient's abdomen. During the operation, the surgical manipulator provides mechanical articulation and control of a variety of surgical instruments, such as tissue graspers, needle drivers, electrosurgical cautery probes, etc., that each perform various functions for the surgeon, e.g., holding or driving a needle, grasping a blood vessel, or dissecting, cauterizing or coagulating tissue.
This new method of performing telerobotic surgery through remote manipulation has, of course, created many new challenges. One such challenge results from the fact that a portion of the electromechanical surgical manipulator will be in direct contact with the surgical instruments, and will also be positioned adjacent the operation site. Accordingly, the surgical manipulator may become contaminated during surgery and is typically disposed of or sterilized between operations. From a cost perspective, it would be preferable to sterilize the device. However, the servo motors, sensors, encoders, and electrical connections that are necessary to robotically control the motors typically cannot be sterilized using conventional methods, e.g., steam, heat and pressure, or chemicals, because the system parts would be damaged or destroyed in the sterilization process.
A sterile drape has been previously used to cover the surgical manipulator and has included holes through which an adaptor (for example a wrist unit adaptor or a cannula adaptor) would enter the sterile field. However, this disadvantageously requires detachment and sterilization of the adaptors after each procedure and also causes a greater likelihood of contamination through the holes in the drape.
Yet another challenge with telerobotic surgery systems is that a surgeon will typically employ a large number of different surgical instruments/tools during a procedure. Since the number of manipulator arms are limited due to space constraints and cost, many of these surgical instruments will be attached and detached from the same manipulator arm a number of times during an operation. In laparoscopic procedures, for example, the number of entry ports into the patient's abdomen is generally limited during the operation because of space constraints as well as a desire to avoid unnecessary incisions in the patient. Thus, a number of different surgical instruments will typically be introduced through the same trocar sleeve during the operation. Likewise, in open surgery, there is typically not enough room around the surgical site to position more than one or two surgical manipulators, and so the surgeon's assistant will be compelled to frequently remove instruments from the manipulator arm and exchange them with other surgical tools.
What is needed, therefore, are improved telerobotic systems and methods for remotely controlling surgical instruments at a surgical site on a patient. In particular, these systems and methods should be configured to minimize the need for sterilization to improve cost efficiency while also protecting the system and the surgical patient. In addition, these systems and methods should be designed to minimize instrument exchange time and difficulty during the surgical procedure. Accordingly, a sterile adaptor and a system for robotic surgery having improved efficiency and cost-effectiveness is highly desirable.